Yet another reason to hate DRM

Regarding battery life:"Those who belong to subscription services such as Napster or Rhapsody have it worse. Music rented from these services arrive in the WMA DRM 10 format, and it takes extra processing power to ensure that the licenses making the tracks work are still valid and match up to the device itself. Heavy DRM not only slows down an MP3 player but also sucks the very life out of them. Take, for instance, the critically acclaimed Creative Zen Vision:M, with a rated battery life of up to 14 hours for audio and 4 hours for video. CNET tested it at nearly 16 hours, with MP3s--impressive indeed. Upon playing back only WMA subscription tracks, the Vision:M scored at just more than 12 hours. That's a loss of almost 4 hours, and you haven't even turned the backlight on yet."

Comments

Yup it's true. I believe this reason for this is quite simple. Inside a portable mp3 player you have many chips. One chip is a hardware audio decoder. That is a chip which converts the digital music into audible music. There is another chip in there which is a general purpose cpu. When you are listening to music and not doing anything else then the general purpose cpu is not really using much power, if any. There is no specialized low-power chip to figure out DRM like there is for decoding mp3s. So when listening to DRM music the normal CPU uses power in addition to the audio decoding chip. Of course, this is just what I've heard, but it makes sense to me.

on a slightly related bit of news: Sony's latest Sonic-Stage (Sony's proprietary music media player and transfer software) upgrade is said to allow complete freedom in transfering songs. Basically you won't be limited to a certain number of transfers for each song.